In the medical field, hemostatic management is very important. When the blood vessel in a living body is damaged, various coagulation factors are activated at that local area and fibrin is ultimately formed to thereby lead to hemostasis. In this process, thrombin is the most important enzyme that acts on fibrinogen so as to convert it into fibrin. Fibrinogen per se, though it is present in blood, has no hemostatic activity. It is upon the action of thrombin that the hemostatic activity is exerted. Namely, thrombin plays the most important role in a hemostatic reaction in a living body.